This repository includes the spot model (spot_model.ipynb) I used in Roquette et al. (2020) for looking at typical amplitudes produced by spot variability in YSOs.

This spot-model for YSOs considering the formulation from Bouvier et al. 1993

$$\Delta m=-2.5\log{\Bigg(1-\frac{f}{1-\frac{\mu}{3}}\Bigg[1-\frac{B_\lambda(T_\mathrm{spot})}{B_\lambda(T_*)}\Bigg]\Bigg)}$$

where:

• $m$ is the magnitude at a filter with an effective wavelength $\lambda$.
• $B_\lambda(T)$ are the value of a Planck-curve for a Black-Body for temperature $T$ at a wavelength $\lambda$.
• $T_{spot}$ and $T_{*}$ are the spot and stellar temperature respectively.
• $f$ is the fraction of coverage by spots.
• $\mu$ is the limb darkening coefficient for that filter

The Limb-darkening values in LimbDarkeningClaret&Blomen_2011.fit are linear limb-darkening coefficients from Claret & Bloemen 2011.

Photometric bands' effective wavelengths are from SVO-database

Typical Spot temperatures for YSOs (Venuti15_spot_parameters.csv) are from Venuti et al. 2015.

@juliaroquette 20 February 2024: Feel free to use it, but please acknowledge the appropriate references mentioned here.